The present invention relates generally to a system for providing modem capabilities in a personal computer. More particularly, this invention relates to a modem assembly that is compatible with standard input/output connectors on PCMCIA cards, which typically are used with a portable personal computer. Still more particularly, the present invention relates to a modem interface connector that attaches to a standard internal DAA (Data Access Arrangement) PCMCIA Modem Card and which mounts flush to the outer housing of the portable personal computer for providing an electrical connection between the PCMCIA Modem Card and a telephone jack.
Within the last few years, PCMCIA cards have become widely used in laptop, notebook and other portable computers. PCMCIA cards are constructed according to certain specifications and standards as set forth by the Personal Computer Memory Card International Association, commonly referred to as PCMCIA PC Card Standards. One standard, for example, is that PCMCIA cards have a 68 pin interface that is received in a card socket mounted in the personal computer for transmitting and receiving electrical signals to and from the computer motherboard.
The first PCMCIA cards were strictly memory cards that were designed to expand the memory of the computer. The PCMCIA cards typically are inserted into a slot or card socket in the computer, much like a conventional floppy disc, except that the card socket has female receptacles to receive the male connection or pins on the PCMCIA card. PCMCIA cards have been introduced that add modem functions and connections, network functions and connections, and numerous other capabilities to the portable computer, in addition to adding memory. Thus, PCMCIA cards provide the user with the capability of adding memory or peripheral devices to the portable computer without the necessity of taking the cover off of the computer to add additional boards or cards.
PCMCIA Modem Cards have become increasingly popular in recent years as a way to link the portable personal computer to telephone lines in order to transmit data to and receive data from a remote computer. Thus, an individual working at home, or who is travelling, can transmit data and facsimiles from a portable personal computer to a computer at a remote facility through the use of a PCMCIA Modem Card. In accordance with conventional techniques, the PCMCIA Modem Card includes input/output (I/O) connectors that electrically connect via a connector interface to a standard RJ-11 telephone jack. The telephone jack typically connects between a telephone line and the telephone itself or an equivalent connector.
As will be understood by one skilled in the art, the Modem Card translates and reconfigures binary signals from the computer into analog signals that are capable of being transmitted over telephone lines. Thus, in accordance with normal convention, a modem at the transmitting computer receives binary digital code from the computer and converts the binary code into modem frequency signals that are transmitted over the telephone lines to a receiving modem. The receiving modem then converts the modem frequency signal back to binary digital code, which is then applied as an input signal to the receiving computer.
Because modems provide an interface between telephone lines and personal computers, the Federal Communications Commission ("FCC") and the telephone companies require that any such interface must be constructed to protect the phone lines and systems from damage to preserve the integrity of transmissions over the telephone lines. In order to comply with these requirements, modems typically include a Data Access Arrangement (DAA) circuit. The DAA circuit protects the telephone line from disabling influences emanating from the computer or modem. The DAA circuit also provides an impedance match and also serves to isolate the modem and the computer from transient signals and other disturbances coming in over the telephone line. An internal DAA circuit may be provided as part of the PCMCIA Modem Card.
Recently, the Personal Computer Memory Card International Association has adopted Modem Card Connector standards in an attempt to standardize the connectors used on internal DAA PCMCIA Modem Cards which interface directly to the telephone system. These standards require a standardized 4-pin electrical input/output connector on the DAA PCMCIA Modem Card and a standardized physical connector arrangement.
Currently, there are two general types of interface connectors that are commercially available to connect the DAA PCMCIA Modem Card to the standard RJ-11 telephone jack. The first type of interface connector requires an external adaptor assembly to connect the PCMCIA Modem Card to the RJ-11 telephone socket. As shown in the prior art drawing of FIG. 1, the first type of interface connector 5 comprises an electrical connector plug 10 that connects physically and electrically to the PCMCIA Modem Card 12 at I/O connectors 15. The interface connector 5 includes an external module 18 that houses an external DAA circuit and an RJ-11 telephone socket 17. An RJ-11 telephone plug (not shown) is inserted into RJ-11 telephone socket 17 to complete the connection to the telephone line. Module 18 connects electrically to the connector plug 10 through a connector cable 16.
The interface connector assembly shown in FIG. 1 has a number of shortcomings. As will be recognized by one skilled in the art, the interface connector 5 shown in FIG. 1 requires the user to carry the adaptor assembly (comprising plug 10, cord 16 and module 18) at all times, and to connect the assembly to the PCMCIA Modem Card 12 when modem capabilities are desired. If the user fails to carry the interface connector, modem capabilities are lost. In addition, because the interface connector assembly 5 of FIG. 1 is mounted externally to the personal computer 11, the assembly requires space in addition to the space occupied by the computer and, furthermore, the assembly is susceptible to being dislodged as the personal computer is repositioned in the work space.
In an attempt to overcome these deficiencies, Megahertz.RTM. has introduced the XJACK.RTM. connector. See U.S. Pat. No. 5,183,404. The XJACK.RTM. connector, shown in FIG. 2, comprises a PCMCIA Card 20 with an RJ-11 telephone socket 25 mounted integrally with the PCMCIA Card 20 on a retractable unit 29. An RJ-11 telephone plug is inserted into RJ-11 telephone socket to complete the connection to the telephone line. The retractable unit 29 extends from the body of the PCMCIA Card 20 by depressing a lever 27 on the side of the PCMCIA Card 20 when modem capabilities are desired. When travelling, or when modem capabilities are unnecessary, the retractable unit 29 can be re-inserted back into the body of the PCMCIA Card 20. See U.S. Pat. No. 5,183,404.
One potential problem with the Megahertz.RTM. XJACK.RTM. connector is that it does not comply with the new standards adopted by the Personal Computer Memory Card International Association because the XJACK.RTM. connector does not include the 4-pin connector for the PCMCIA Card, nor can one be added because of the position of the integral RJ-11 telephone socket. As such, the Megahertz.RTM. XJACK.RTM. connector does not use the PCMCIA standard connector and interface. In addition, because the RJ-11 telephone socket 25 in the Megahertz.RTM. design extends from the body of the personal computer when in use, there exists a possibility that the socket 25 could be damaged or broken as the computer is repositioned by the user.
There is no PCMCIA modem system in use today that offers an integral RJ-11 telephone socket in an interface connector assembly that complies with current PCMCIA standards. Faced with these shortcomings in the industry, it would be advantageous to develop a modem connector interface that mounts integrally to the PCMCIA Modem Card without the necessity of additional connections or external adaptor cords. It also would be advantageous to develop a connector interface for an internal DAA PCMCIA Modem Card that mounts flush to the housing of the personal computer.
These and other advantages and features of the present invention will become apparent upon a reading of the description of the preferred embodiment provided herein.